Center a rack in the oven and preheat the oven to 350° F. Line a baking sheet with a silpat or parchment paper. In a small bowl, whisk together the flour, baking powder, and salt. Add the cornmeal and whisk again to blend.

step 2: HideShow Images

In the bowl of a stand mixer fitted with the paddle attachment, beat the butter and sugar together at medium speed for 3 minutes, until very smooth. Add the eggs and continue to beat, scraping down the bowl as needed, for another 2 minutes or until the mixture is light, smooth and creamy. Beat in the almond extract. Reduce the mixer speed to low and add the dry ingredients, mixing just until they are incorporated. The dough will be sticky. Scrape down the paddle and bowl, add in the sliced almonds and mix just until blended in.

step 3: HideShow Images

Scrape half of the dough onto one side of the baking sheet. Using a rubber spatula or your fingers (I like to cover my hand with lightly oiled plastic wrap), form the dough into a log about 12 inches long and 1½ inches wide. The log will be rectangular, with a bumpy and uneven surface. Form a second similar log on the other side of the baking sheet.

step 4: HideShow Images

Bake for 15-20 minutes, or until the logs are lightly golden but still soft and springy to the touch. Transfer the baking sheet to a rack and cool the logs on the baking sheet for 30 minutes.

step 5: HideShow Images

(If you turned the oven off, return it to 350° F.) Using a long serrated knife, cut the logs into 1-inch thick slices. Turn the slices so that they stand on their sides, and return the sheet to the oven.

step 6: HideShow Images

Bake the biscotti for another 15-20 minutes, or until they are golden and firm. Transfer them to wire racks to cool completely.